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Date: Thu, 2 Aug 2007 18:13:49 +0100
From: Alan Cox <alan@lxorguk.ukuu.org.uk>
To: Mark Lord <lkml@rtr.ca>
Cc: Robert Hancock <hancockr@shaw.ca>,
       "Maciej W. Rozycki" <macro@linux-mips.org>,
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       Lee Howard <faxguy@howardsilvan.com>, linux-serial@vger.kernel.org,
       tytso@mit.edu, linux-kernel@vger.kernel.org
Subject: Re: serial flow control appears broken
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> That's what "hdparm -u1" (or -u0) controls.

Only some of the time.

> Ingo's RT patches would probably fix all of this.

The worst case IDE times we've seen for executing a single indivisible
un-interruptible I/O cycle with a drive are around 1mS. Thats a hardware
limit.

Alan
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